1. Field of the Invention
The present invention relates to a gas-liquid separating apparatus. More particularly, the present invention relates to a gas-liquid separating apparatus which can easily separate bubbles from liquid of which a hot-water line enables the circulation by a pump in a heating system such as a gas boiler.
2. Prior art
Generally, gas boilers having a hot-water heating system using heated water are widely used at home. In these systems, a small number of bubbles pass through a hot-water line together with liquid in the hot water line wherein the liquid flows or circulates by the pump. When such bubbles contained in the liquid circulate through the hot-water heating line at the same time when a fluid flows therethrough, it causes the pump cavitation and therefore, the pump efficiencies are lowered. Further, it becomes the reasons of a break-down in the system, and the heat transfer is hindered to reduce the whole thermal efficiency of the heating system. Therefore, it will be preferable to easily and efficiently separate the bubbles from the liquid.
Conventionally, to separate the bubbles from the liquid, there has been proposed a gas-liquid separating apparatus using the concentric force of the liquid. FIG. 1 is a perspective view for showing a conventional gas-liquid separating apparatus and FIG. 2 is a plan sectional view taken along line A-A' of FIG. 1. As shown in FIGS. 1 and 2, the conventional gas-liquid separating apparatus is provided with a cylindrical gas-liquid separating barrel 2 which has a cylindrical gas-liquid separating space 1 having an air vent hole 6 formed at the center upper portion thereof. An air vent (not shown) is mounted on the upper portion of air vent hole 6. A liquid introducing tube 3 is formed on an upper portion of gas-liquid separating barrel 2 in the direction of a tangent line. A liquid exhaust tube 4 is formed on a lower portion of the opposite side thereof in the opposite direction of the above tangent line. A conical rod 5 is installed at the center of the inside of cylindrical gas-liquid separating space 1.
A fluid is introduced into barrel 2 through liquid introducing tube 3 and then out through liquid exhaust tube 4 formed on the lower portion of the opposite side thereof. At this time, as shown in FIGS. 1 and 2, the fluid is rotated in the direction of the arrow in gas-liquid separating barrel 2 and flows directly to liquid exhaust tube 4 from liquid introducing tube 3. Since a part of liquid without bubbles which is introduced through liquid introducing tube 3 has a relatively high density compared with another part of the liquid with bubbles, the first parts of liquids without bubbles flow along the outer lines apart from the center portion of gas-liquid separating barrel while the second parts of liquid with bubbles flow centering around conical rod 5. At this time, small bubbles contained in the liquid collide with one another to grow in size. The bigger bubbles are separated from the liquid to ascend upwards. The isolated bubbles are drawn out through air vent hole 6 having an air vent (not shown) disposed at the upper portion thereof.
The air vent is such a device that, when the volume of the air which has been isolated from the water and collected therein exceeds a predetermined value, a valve thereof opens and selectively vents the collected bubbles out through air vent hole 6. This air vent is widely known and easily available in markets. In this manner, the bubbles can be removed from the liquid.
The gas-liquid separating apparatus performs separation of bubbles from liquid using the centrifugal separating manner according to density difference of the liquid. Therefore, for the purpose of performance of centrifugal separation, a gas-liquid separating barrel having a separation space of a sufficiently large volume is necessary. In order to install such a gas-liquid separating barrel in a gas boiler, an additional space in the gas boiler is necessary, which results in a bulky gas boiler. In addition, the gas-liquid separating barrel gets in the way of other neighboring components, so that it is relatively difficult to manufacture the gas boiler, and it raises the cost of the gas boiler as well.